Vulnerability in Kernel (CVE-2024-44991)

Summary

Vulnerability in Kernel (CVE-2024-44991). Risk of unauthorized operations or information disclosure. Mitigation: upgrade to 6.1.107, 6.6.48, 6.10.7 or later.

Original description

The description as published by the source.

In the Linux kernel, the following vulnerability has been resolved:

tcp: prevent concurrent execution of tcp_sk_exit_batch

Its possible that two threads call tcp_sk_exit_batch() concurrently,
once from the cleanup_net workqueue, once from a task that failed to clone
a new netns. In the latter case, error unwinding calls the exit handlers
in reverse order for the 'failed' netns.

tcp_sk_exit_batch() calls tcp_twsk_purge().
Problem is that since commit b099ce2602d8 ("net: Batch inet_twsk_purge"),
this function picks up twsk in any dying netns, not just the one passed
in via exit_batch list.

This means that the error unwind of setup_net() can "steal" and destroy
timewait sockets belonging to the exiting netns.

This allows the netns exit worker to proceed to call

WARN_ON_ONCE(!refcount_dec_and_test(&net->ipv4.tcp_death_row.tw_refcount));

without the expected 1 -> 0 transition, which then splats.

At same time, error unwind path that is also running inet_twsk_purge()
will splat as well:

WARNING: .. at lib/refcount.c:31 refcount_warn_saturate+0x1ed/0x210
...
refcount_dec include/linux/refcount.h:351 [inline]
inet_twsk_kill+0x758/0x9c0 net/ipv4/inet_timewait_sock.c:70
inet_twsk_deschedule_put net/ipv4/inet_timewait_sock.c:221
inet_twsk_purge+0x725/0x890 net/ipv4/inet_timewait_sock.c:304
tcp_sk_exit_batch+0x1c/0x170 net/ipv4/tcp_ipv4.c:3522
ops_exit_list+0x128/0x180 net/core/net_namespace.c:178
setup_net+0x714/0xb40 net/core/net_namespace.c:375
copy_net_ns+0x2f0/0x670…

Source: OSV.dev (Open Source Vulnerabilities) NVD OSV

Auto-generated summary

Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.

A vulnerability tracked as CVE-2024-44991 has been found in Kernel.
Risk of unauthorized operations or information disclosure.
What to do: upgrade Kernel to 6.1.107, 6.6.48, 6.10.7 or later.
If unsure, ask your IT team or search "Kernel CVE-2024-44991" on the vendor's site.

CVE-2024-44991 (Kernel)
Patched: 6.1.107, 6.6.48, 6.10.7 — apply immediately
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.

❓ What is the problem

A vulnerability (unclassified) exists in Kernel.

📍 Affected scope

Check the vendor advisory for the affected versions of Kernel.

🔥 Severity

Severity: ?. Risk of unauthorized operations or information disclosure.

🔧 How to fix

Update to 6.1.107, 6.6.48, 6.10.7.

🛡️ Workaround

Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.

🔍 Detection

Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'Kernel' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.

Response actions

Concrete steps and command examples for SOC/SRE teams to execute in order

1
Identify exposure identify
```
grep -r 'Kernel' . | grep -v node_modules
```
リポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で Kernel を grep し、稼働しているサービス・バージョンを把握する。
2
Apply patch patch
```
Upgrade Kernel to 6.1.107, 6.6.48, 6.10.7
```
ステージング環境で 6.1.107, 6.6.48, 6.10.7 に上げて回帰テスト → 本番反映。回帰テストはアプリの主要ハッピーパスを含めること。
3
Post-deployment verification verify
```
Confirm patched version is live in production
```
パッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。

Affected packages

Linux Kernel

[{"type":"ECOSYSTEM","events":[{"introduced":"6.1.0"},{"fixed":"6.1.107"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.2.0"},{"fixed":"6.6.48"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.7.0"},{"fixed":"6.10.7"}]}]

Fix status by distribution

Fixed packages published by each distribution for this CVE

Debian DEBIAN-CVE-2024-44991 linux Fixed in: 6.1.112-1